Under certain growth conditions, maples produce wood with a curly grain structure known as flaming or fiddleback. Such wood used for back plates makes for a lively, almost three-dimensional structure. If a clear ground coat and transparent varnish are used, light is refracted as the instrument is tilted, creating the illusion of depth. Flamed maple or tiger maple is the wood of choice in violinmaking for its beautiful appearance. The use of flamed or unflamed wood makes no discernible difference to tonal quality.